Table 1.
Success ratio as a function of the base rate (BR), selection ratio (SR) and low predictor-criterion correlation.
| BR=0.70 | BR=0.80 | BR=0.90 | |||||||
|---|---|---|---|---|---|---|---|---|---|
| SR | R=0.07 | R=0.17 | Δ | R=0.07 | R=0.17 | Δ | R=0.07 | R=0.17 | Δ |
| 0.60 | 71.6 | 73.9 | 2.3 | 81.3 | 83.1 | 1.8 | 90.8 | 92.0 | 1.2 |
| 0.30 | 72.8 | 76.7 | 3.9 | 82.2 | 85.3 | 3.1 | 91.4 | 93.3 | 1.9 |
| 0.10 | 74.2 | 79.8 | 5.6 | 83.3 | 87.6 | 4.3 | 92.0 | 94.5 | 2.5 |
| 0.05 | 74.9 | 81.2 | 6.3 | 83.8 | 88.6 | 4.8 | 92.3 | 95.1 | 2.8 |
ΔR2=(0.17)2–(0.07)2=0.0289–0.0049≈0.024; Δ denotes the differences in more successful decisions when the multiple correlation increase from R=0.07 to R=0.17 (or equivalently ΔR2≈0.024).